Update dependency versions.

- k8s client-go v0.25.5
- Build with go 1.19

While here:
- prometheus client v1.15.1
- logrus v1.9.0

container/Dockerfile

 ARG varnish_version=6.6.2
+ARG go_version=1.19.9
 
 # Build container
-FROM debian:buster-20220125-slim AS builder
+FROM golang:${go_version}-buster AS builder
 
 RUN apt-get update -q && \
     apt-get install -y -q debian-archive-keyring && \
@@ -9,13 +10,11 @@ RUN apt-get update -q && \
     curl -L https://packagecloud.io/varnishcache/varnish66/gpgkey | apt-key add -
 
 ARG varnish_version
-ARG go_version=1.15
+ARG go_version
 COPY ./container/varnishcache_varnish66.list /etc/apt/sources.list.d/
-COPY ./container/buster-backports.list /etc/apt/sources.list.d/
 RUN apt-get update -q && \
     apt-get install -y -q varnish-dev=${varnish_version}-1~buster && \
-    apt-get -t buster-backports install -y -q golang-${go_version}-go && \
-    apt-get -t buster-backports install -y -q golang-golang-x-tools && \
+    apt-get install -y -q golang-golang-x-tools && \
     apt-get install -y -q git make && \
     apt-get remove -y -q curl gnupg apt-transport-https && \
     apt-get autoremove -y -q && apt-get clean && rm -rf /var/lib/apt/lists/*
@@ -24,6 +23,7 @@ ENV GOPATH=/go
 ENV GOSRC=${GOPATH}/src
 ENV PATH=${PATH}:/usr/lib/go-${go_version}/bin:${GOPATH}/bin
 RUN mkdir -p ${GOPATH}
+ENV GO111MODULE=off
 RUN go get -d -v github.com/slimhazard/gogitversion && \
     cd ${GOSRC}/github.com/slimhazard/gogitversion && \
     make install

go.mod

 module code.uplex.de/uplex-varnish/k8s-vcl-reloader
 
-go 1.15
+go 1.19
 
 require (
 	code.uplex.de/uplex-varnish/varnishapi v0.0.0-20191205154529-31e610a4139d
-	github.com/prometheus/client_golang v1.2.1
-	github.com/sirupsen/logrus v1.4.2
-	k8s.io/api v0.20.13
-	k8s.io/apimachinery v0.20.13
-	k8s.io/client-go v0.20.13
+	github.com/prometheus/client_golang v1.15.1
+	github.com/sirupsen/logrus v1.9.0
+	k8s.io/api v0.25.5
+	k8s.io/apimachinery v0.25.5
+	k8s.io/client-go v0.25.5
 )
 
-require github.com/imdario/mergo v0.3.6 // indirect
+require (
+	github.com/PuerkitoBio/purell v1.1.1 // indirect
+	github.com/PuerkitoBio/urlesc v0.0.0-20170810143723-de5bf2ad4578 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/emicklei/go-restful/v3 v3.8.0 // indirect
+	github.com/go-logr/logr v1.2.3 // indirect
+	github.com/go-openapi/jsonpointer v0.19.5 // indirect
+	github.com/go-openapi/jsonreference v0.19.5 // indirect
+	github.com/go-openapi/swag v0.19.14 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/google/gnostic v0.5.7-v3refs // indirect
+	github.com/google/go-cmp v0.5.9 // indirect
+	github.com/google/gofuzz v1.1.0 // indirect
+	github.com/imdario/mergo v0.3.6 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/mailru/easyjson v0.7.6 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/prometheus/client_model v0.3.0 // indirect
+	github.com/prometheus/common v0.42.0 // indirect
+	github.com/prometheus/procfs v0.9.0 // indirect
+	github.com/rogpeppe/go-internal v1.10.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	golang.org/x/net v0.7.0 // indirect
+	golang.org/x/oauth2 v0.5.0 // indirect
+	golang.org/x/sys v0.6.0 // indirect
+	golang.org/x/term v0.5.0 // indirect
+	golang.org/x/text v0.7.0 // indirect
+	golang.org/x/time v0.0.0-20220210224613-90d013bbcef8 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/protobuf v1.30.0 // indirect
+	gopkg.in/inf.v0 v0.9.1 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+	k8s.io/klog/v2 v2.70.1 // indirect
+	k8s.io/kube-openapi v0.0.0-20220803162953-67bda5d908f1 // indirect
+	k8s.io/utils v0.0.0-20220728103510-ee6ede2d64ed // indirect
+	sigs.k8s.io/json v0.0.0-20220713155537-f223a00ba0e2 // indirect
+	sigs.k8s.io/structured-merge-diff/v4 v4.2.3 // indirect
+	sigs.k8s.io/yaml v1.2.0 // indirect
+)